![]() The julianday() and strftime() functions provide alternate ways to format datetime values. Next, let’s look at other useful date functions like julianday(), strftime(), etc. This provides flexibility to store dates in compact formats but convert to human-readable datetimes when required. We can use datetime() to convert between storage formats: SELECTĭatetime(julianday(' 09:30:45')) AS julianday_format,ĭatetime(strftime('%s',' 09:30:45')) AS unix_format This provides an easy way to do date math in SQLite queries! Converting Datetime Storage Formats in SQLite We can use modifiers with datetime() to perform arithmetic on dates/times: SELECTĭatetime(' 09:30:45', '-1 day') AS yesterday,ĭatetime(' 09:30:45', '+1 month') AS next_month These are convenient for extracting the required date or time component from a datetime value. The time() function returns just the time part: SELECT time(' 09:30:45') The date() function returns just the date part of a datetime: SELECT date(' 09:30:45') SQLite also provides separate date() and time() functions: date() To format a date/time string: SELECT datetime(' 09:30:45') To get the current date/time: SELECT datetime('now') Let’s see some examples: Formatting Dates and Times in SQLite It accepts a date/time value as the first argument followed by optional modifiers. The syntax is: datetime(timestring, modifier, modifier. Perform date arithmetic using modifiers.The most versatile date/time function in SQLite is datetime(). Now let’s look at how to use SQLite’s date and time functions to manipulate datetime values efficiently. ![]() For most use cases, storing as ISO-8601 strings provides the best balance in terms of human readability, storage efficiency and date manipulations using SQLite’s date functions. Limited range -Unable to store dates before 1970Īs we can see, each storage format has trade-offs.To make the timestamp human-readable: SELECTĭatetime(meeting_unixtime, 'unixepoch') AS meeting_datetime SQLite can also store datetimes as the UNIX timestamp – the number of seconds since the Unix epoch 00:00:00 UTC. Require conversion for human readability.When queried with the SELECT statement, we need to convert the Julian day number back to a human-readable datetime: SELECTĭatetime(meeting_datetime) AS meeting_datetime The Julian day number represents the number of days since noon UTC on NovemBCE in the proleptic Gregorian calendar. SQLite can store dates and times as Julian day numbers in the REAL type. Requires parsing and reformatting for computations.Allows storing just the date or time part if required.Id title meeting_date start_time end_time This stores the dates and times as formatted strings that are human-readable when queried: SELECT * FROM meetings To store a date, time or datetime as TEXT, use the ISO-8601 formats: SQLite allows storing date/time values as TEXT, REAL or INTEGER:Įach approach has pros and cons. SQLite Datetime functions Storing Dates and Times in SQLite Here is a quick comparison of the main datetime functions in SQLite: FunctionĬonverts values, handles modifiers and date math ![]() Let’s get started! Quick Overview of Datetime Functions in SQLite To illustrate the examples, we will use a sample database of an e-commerce site that contains orders, products and customer info.
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